Conventionally, a portable audio output device which is placed on a user's ear such as an earphone is used. Conventional portable audio output devices include one having a hook-shaped hanger unit which is hooked over a user's external ear and one having a frame-shaped hanger unit surrounding an external ear (see, for example, Patent Document 1). In the conventional portable audio output devices, the hanger units are formed of a resin such as a plastic.